The present invention relates to a new and distinct cultivar of Hydrangea macrophylla, a member of the Hydrangeaceae family, hereinafter referred to by its cultivar name ‘PIIHM-I’. This cultivar is grown primarily as an ornamental for landscape use and for use as a potted plant. The cultivar originated from controlled cross-pollination of Hydrangea macrophylla ‘Penny Mac’ (unpatented) by Hydrangea macrophylla ‘Lady in Red’ (U.S. Plant Pat. No. 15,175) in Athens, Ga. in 2003, and was selected from the progeny seedlings of this cross by continued evaluation for reblooming, increased resistance to mildew, and improved leaf and flower characteristics.
‘PIIHM-I’ has been asexually reproduced by softwood cuttings since 2004 in Athens, Ga. and in Watkinsville, Ga. The characteristics of the cultivar have been stable and reproduced true to type in successive vegetative generations.
‘PIIHM-I’ is distinguished from its female parent ‘Penny Mac’ by its lacecap inflorescence, flower color, foliage color, fall color, stem color, and its increased resistance to powdery mildew, and from its male parent ‘Lady in Red’ by its reblooming trait, flower color, and stem color. ‘PIIHM-I’ has bright pink lacecap inflorescences in non-aluminum media and pink-purple inflorescences in aluminum media, whereas ‘Penny Mac’ and ‘Lady in Red’ produce pink inflorescences in non-aluminum media and blue inflorescences in aluminum media. ‘PIIHM-I’ has thicker, darker green leaves than ‘Penny Mac’. The leaves of ‘PIIHM-I’ develop orange to rich rose-red to red-purple fall color whereas leaves of ‘Penny Mac’ turn yellow or senesce green to brown. ‘PIIHM-I’ has pink-red stems, whereas ‘Penny Mac’ has green stems and ‘Lady in Red’ has red stems. There are no other reblooming cultivars of Hydrangea macrophylla with bright pink lacecap inflorescences known to the inventor.